Table 3.

Univariate Classification of Human Osteochondral Plugs by OARSI Grade.

		Training Set			Validation Set
ROI	MRI Measurement	Sensitivity	Specificity	Accuracy	Sensitivity	Specificity	Accuracy
Superficial	DW (b = 2000 s/mm2)	0.76 ± 0.00	0.60 ± 0.04	0.68 ± 0.02	0.75 ± 0.02	0.59 ± 0.04	0.67 ± 0.03
	MTR	0.58 ± 0.01	0.75 ± 0.04	0.67 ± 0.02	0.58 ± 0.02	0.73 ± 0.05	0.66 ± 0.03
	T2 3D (ms)	0.62 ± 0.07	0.71 ± 0.04	0.67 ± 0.04	0.58 ± 0.07	0.69 ± 0.06	0.63 ± 0.04
Deep	T1W	0.70 ± 0.02	0.67 ± 0.04	0.68 ± 0.02	0.68 ± 0.04	0.67 ± 0.05	0.67 ± 0.03
	MTR	0.52 ± 0.06	0.76 ± 0.04	0.64 ± 0.04	0.51 ± 0.06	0.76 ± 0.04	0.64 ± 0.04
	T2W (TE = 70 ms)	0.61 ± 0.03	0.65 ± 0.06	0.63 ± 0.05	0.56 ± 0.06	0.65 ± 0.06	0.61 ± 0.05
Full	T1W	0.75 ± 0.02	0.66 ± 0.05	0.71 ± 0.03	0.73 ± 0.04	0.64 ± 0.06	0.69 ± 0.05
	T2 3D (ms)	0.58 ± 0.02	0.77 ± 0.04	0.68 ± 0.02	0.53 ± 0.02	0.77 ± 0.04	0.65 ± 0.02
	MTR	0.53 ± 0.01	0.78 ± 0.04	0.65 ± 0.03	0.53 ± 0.02	0.78 ± 0.04	0.65 ± 0.03

Univariate classification of human osteochondral plugs grouped by OARSI grade for the top three performing MRI measurements in superficial, deep, and full-thickness ROIs. Sensitivity, specificity, and accuracy are reported as the means and standard deviations over 100 random selections of training sets and validation sets of equal size normal (n = 23) and diseased (n = 17) groups using the Mahalanobis distance metric and leave-one-out cross-validation method.